The multifunction peripherals in recent years very often use computers (including personal computers) in which are installed general purpose operating systems as control systems, and are compatible with networks. Due to such adapting to PCs, the danger of multifunction peripherals to be infected by computer viruses is becoming high and the possibility of spreading the infection to other equipment is increasing, and antivirus measures are being taken.
For example, since very often a computer virus shows the behavior of spreading the infection to external terminals or severs, etc., there are technologies in which the presence or absence of virus infection is detected based on the operation of the multifunction peripheral communicating with the outside. In detailed terms, the control system inside the multifunction peripheral monitors the periodicity of communication with an external apparatus, detects abnormal communication operation by comparing the communication periodicity with a threshold value set in advance, decides that there is infection by a computer virus if the communication periodicity exceeds the threshold value, and carried out that detection as well as removal of viruses (see Unexamined Japanese Patent Application Publication No. 2004-302656).
In the method of detecting the presence or absence of virus infection by monitoring the actual operation as described above, if the multifunction peripheral is already infected, it operates in the infected state, and hence it is possible that damage is caused by the computer virus. For example, in the method of detecting by comparing the communication periodicity with a threshold value, even when the multifunction peripheral is in the infected state, since communication is carried out without detecting the virus until the communication periodicity exceeds the threshold value, when the communication periodicity exceeds the threshold value and virus infection is detected, it is likely that already infected data has been transmitted and the infection is spread. Therefore, with this technology, the virus countermeasure is not sufficient.
Further, when a virus check is made by a program, the method of pattern matching, etc., is very common in which the characteristic part within the virus code taken out as a pattern and is built up as a database, and the data stored in the storage region (the virus check target data) is compared with the database thereby finding out computer viruses.
However, in embedded equipment such as the above multifunction peripheral, unlike a general purpose personal computer, the resources such as the CPU (Central Processing Unit) or the memory are not plentiful due to cost reduction. If virus scan is executed by a virus checking program having a high processing load during job processing or during user operation, the processing speed decreases substantially. Because of this, it is difficult to carry out virus checks periodically and frequently irrespective of the processing due to jobs or user operations, and when infected by a computer virus, detecting that is likely to be delayed.
Therefore, in embedded equipment, a technology is desired that carries out virus checks efficiently, in which virus checking is not carried out periodically and frequently irrespective of the presence or absence of virus infection, but detection is made of the likelihood of virus infection without obstructing the processing, and also, before any damage occurs due to computer viruses, and virus check is made at appropriate timings.
Further, not only in embedded equipment, but also in job processing apparatuses in which the resources are relatively plentiful, since the processing (performance) is likely to get reduced if the virus check program is executed, similarly it is desirable that it is possible to execute virus checks in an efficient manner.
The present invention was made for solving the above problem, and an object of the present invention is to provide a job processing system and an image processing apparatus in which it is possible to determine, without obstructing the processing and before any damage is done by a computer virus, whether or not a virus check is necessary.